Speaking to the Official Club Website, the defender who played under Royle at Everton admitted: "The main attraction for me coming to Ipswich was the chance to work with Joe again.
"I know Joe and Willie Donachie very well from our days together at Everton and had great times under their management. They know me inside out and hopefully we can enjoy our time together here at Ipswich as well.
"The move came out of the blue really. The two chairman did the deal and I was told I could go which caught me out a bit.
"I got injured after the new manager came in at Portsmouth and was on the sidelines for three or four weeks and when I returned to fitness, the team was doing okay and it was hard to break back into the side.
"But what has happened this season at Portsmouth has been like a soap opera and it will be nice to come to a club where it's a bit quieter off the pitch and we can just concentrate on playing football.
"I know a few of the lads here, Jim Magilton and Kevin Horlock are two I've played against a few times and I'm looking forward to training with the players this week and hopefully playing my part on Saturday.
"I'm here until the end of the season and hopefully I can play a role in helping Ipswich win promotion to the Premiership. After that, I'm not sure what my future will be. A lot will depend on what Portsmouth say."